Diagnostic Microbiology and Infectious Disease, 2004
The presence of Trypanosoma cruzi in chronic chagasic patients with negative xenodiagnosis (XD) a... more The presence of Trypanosoma cruzi in chronic chagasic patients with negative xenodiagnosis (XD) after 6 years following completion of therapy with either itraconazole or allopurinol was assessed by polymerase chain reaction (PCR) and hybridization assays. A 330-bp DNA fragment amplified from the hypervariable regions of T. cruzi kinetoplastid minicircles was hybridized with total 32P-labeled kinetoplast DNA as probes. PCR alone enabled the identification of T. cruzi nucleotide sequences in 40% of the patients treated with itraconazole and in 60% of patients treated with allopurinol. PCR used in combination with hybridization detected parasite DNA in 60% and 53% of XD negative individuals treated with itraconazole or allopurinol, respectively. These results show that PCR and hybridization are more sensitive than conventional parasitological techniques in diagnosing patients that have undergone chemotherapy with itraconazole or allopurinol.
In this paper we present an unsupervised model for learning arbitrary relations between concepts ... more In this paper we present an unsupervised model for learning arbitrary relations between concepts of a molecular biology ontology for the purpose of supporting text mining and manual ontology building. Relations between named-entities are learned from the GENIA corpus by means of several standard natural language processing techniques. An in-depth analysis of the output of the system shows that the model is accurate and has good potentials for text mining and ontology building applications. * We would like to thank our colleagues in the Laboratory for Applied Ontology (LOA-CNR), and the Klaus Tschira Foundation for their financial support.
An instrument was designed and assembled with the aim of measuring macroscopic properties of foam... more An instrument was designed and assembled with the aim of measuring macroscopic properties of foams (such as foamability and stability) under high pressures and moderate temperatures (up to 105 bar and 425 K, respectively). The device makes use of infrared sensors to detect the foam forefront position as it is generated by gas sparging in the foaming solution. The measurement
Begomoviruses were detected in Nicaraguan fields of tomato (Lycopersicon esculentum) and adjacent... more Begomoviruses were detected in Nicaraguan fields of tomato (Lycopersicon esculentum) and adjacently growing plants of pepper (Capsicum annuum), chilli pepper (C. baccatum), cushaw (Cucurbita argyrosperma) and Mexican fireplant (Euphorbia heterophylla) using polymerase chain reaction (PCR) and universal begomovirus primers. All tomato and Mexican fireplant plants showing symptoms were infected with begomoviruses, while only 30–46% of the pepper, chilli pepper and cushaw plants showing symptoms tested virus-positive. No begomoviruses were found in potato. The virus species were provisionally identified by sequencing 533 bp of the viral coat protein gene (AV1). Tomato severe leaf curl virus (ToSLCV), Tomato leaf curl Sinaloa virus (ToLCSinV) and Pepper golden mosaic virus (PepGMV) were found to infect both tomato and pepper. A new provisional species designated Tomato leaf curl Las Playitas virus (ToLCLPV) was detected in a tomato plant. Squash yellow mottle virus (SYMoV) and PepGMV were found in cucurbits, the latter for the first time in this host. Euphorbia mosaic virus (EuMV) was detected in Mexican fireplant. Sequencing of a larger number of PCR-amplified clones from selected plants revealed intraspecific viral sequence variability, and also multiple begomovirus infections which could represent up to three species in a single tomato or cushaw plant. Phylogenetic grouping of virus sequences did not correlate with the host of origin.
Diseases caused by begomoviruses (family Geminiviridae, genus Begomovirus) constitute a serious c... more Diseases caused by begomoviruses (family Geminiviridae, genus Begomovirus) constitute a serious constraint to tomato production in Nicaragua. In this study, the complete nucleotide (nt) sequences of the DNA-A and DNA-B components were determined for the first time for Tomato leaf curl Sinaloa virus (ToLCSinV). In addition, the complete nt sequence was determined for the DNA-A component of two isolates of Tomato severe leaf curl virus (ToSLCV). The genome organization of ToLCSinV and ToSLCV was identical to the bipartite genomes of other begomoviruses described from the Americas. A phylogenetic analysis of DNA-A including 45 begomovirus species showed that the indigenous begomoviruses of the New World can be divided into three major clades and an intermediate group: AbMV clade, SLCV clade, “Brazil clade”, and BGYMV group. Phylogenetic analyses of the DNA-A and DNA-B components and their open reading frames indicated that ToLCSinV and ToSLCV belong to different clades: ToLCSinV to the AbMV clade, and ToSLCV to the SLCV clade. The two Nicaraguan isolates of ToSLCV showed a close relationship with ToSLCV from Guatemala (ToSLCV-[GT96-1]) and Tomato chino La Paz virus (ToChLPV), but differed significantly in the AV1 and AC1 regions, respectively. Computer-based predictions indicated that recombination with another begomovirus had taken place within AV1 of ToSLCV dividing this species into two strains. A high probability was also found that ToChLPV is involved in the evolution of ToSLCV.
and other tomato-growing areas of the world. The disease is caused by several virus species belon... more and other tomato-growing areas of the world. The disease is caused by several virus species belonging to the genus Begomovirus, family Geminiviridae that are transmitted by the whitefly Bemisia tabaci. There has been no previous information about which virus species/strains occur in tomatoes with TYLCD in Turkey. Therefore, polymerase chain reaction tests using degenerate primers were used to amplify partial sequences (579 bp) of the begomovirus coat protein gene (V1) from samples of diseased tomato plants collected from two major tomato-growing areas of Turkey (Mersin and Mug la). DNA sequence analyses of three isolates revealed high nucleotide sequence identities to isolates of Tomato yellow leaf curl virus (TYLCV, 97-98%) and tentatively identified them as belonging to that species. In addition, the complete nucleotide sequence was determined for one TYLCV isolate from Mersin (TYLCV-[TR:Mer6:04]). This isolate showed high nucleotide identity (98%) to isolates from the "prototype" strain of TYLCV, and only 92% identity to isolates of the TYLCV mild strain. A phylogenetic analysis confirmed that TYLCV-[TR:Mer6:04] belonged to the widespread "prototype" strain.
ANTECEDENTES HISTORICOS Desde antes de asumir la presidencia, el gobierno de Salvador Allende est... more ANTECEDENTES HISTORICOS Desde antes de asumir la presidencia, el gobierno de Salvador Allende estuvo marcada por un halo trágico. No sólo era la cuarta vez consecutiva que se presentaba a las elecciones presidenciales, sino que, la única vez que logró la mayoría de los votos (y con esto el cargo de presidente) fue con apenas un tercio de la población. A esto se le sumaba el hecho de que la clase que lo apoyaba no era la más influyente política ni económicamente. Con todos estos datos se podía predecir que la cuesta no se le haría fácil al líder comunista. Debería enfrentarse a dos tercios del país que eran opositores a su postura, entre los cuales se contaban los personajes más destacados e influyentes de la sociedad.
Diagnostic Microbiology and Infectious Disease, 2004
The presence of Trypanosoma cruzi in chronic chagasic patients with negative xenodiagnosis (XD) a... more The presence of Trypanosoma cruzi in chronic chagasic patients with negative xenodiagnosis (XD) after 6 years following completion of therapy with either itraconazole or allopurinol was assessed by polymerase chain reaction (PCR) and hybridization assays. A 330-bp DNA fragment amplified from the hypervariable regions of T. cruzi kinetoplastid minicircles was hybridized with total 32P-labeled kinetoplast DNA as probes. PCR alone enabled the identification of T. cruzi nucleotide sequences in 40% of the patients treated with itraconazole and in 60% of patients treated with allopurinol. PCR used in combination with hybridization detected parasite DNA in 60% and 53% of XD negative individuals treated with itraconazole or allopurinol, respectively. These results show that PCR and hybridization are more sensitive than conventional parasitological techniques in diagnosing patients that have undergone chemotherapy with itraconazole or allopurinol.
In this paper we present an unsupervised model for learning arbitrary relations between concepts ... more In this paper we present an unsupervised model for learning arbitrary relations between concepts of a molecular biology ontology for the purpose of supporting text mining and manual ontology building. Relations between named-entities are learned from the GENIA corpus by means of several standard natural language processing techniques. An in-depth analysis of the output of the system shows that the model is accurate and has good potentials for text mining and ontology building applications. * We would like to thank our colleagues in the Laboratory for Applied Ontology (LOA-CNR), and the Klaus Tschira Foundation for their financial support.
An instrument was designed and assembled with the aim of measuring macroscopic properties of foam... more An instrument was designed and assembled with the aim of measuring macroscopic properties of foams (such as foamability and stability) under high pressures and moderate temperatures (up to 105 bar and 425 K, respectively). The device makes use of infrared sensors to detect the foam forefront position as it is generated by gas sparging in the foaming solution. The measurement
Begomoviruses were detected in Nicaraguan fields of tomato (Lycopersicon esculentum) and adjacent... more Begomoviruses were detected in Nicaraguan fields of tomato (Lycopersicon esculentum) and adjacently growing plants of pepper (Capsicum annuum), chilli pepper (C. baccatum), cushaw (Cucurbita argyrosperma) and Mexican fireplant (Euphorbia heterophylla) using polymerase chain reaction (PCR) and universal begomovirus primers. All tomato and Mexican fireplant plants showing symptoms were infected with begomoviruses, while only 30–46% of the pepper, chilli pepper and cushaw plants showing symptoms tested virus-positive. No begomoviruses were found in potato. The virus species were provisionally identified by sequencing 533 bp of the viral coat protein gene (AV1). Tomato severe leaf curl virus (ToSLCV), Tomato leaf curl Sinaloa virus (ToLCSinV) and Pepper golden mosaic virus (PepGMV) were found to infect both tomato and pepper. A new provisional species designated Tomato leaf curl Las Playitas virus (ToLCLPV) was detected in a tomato plant. Squash yellow mottle virus (SYMoV) and PepGMV were found in cucurbits, the latter for the first time in this host. Euphorbia mosaic virus (EuMV) was detected in Mexican fireplant. Sequencing of a larger number of PCR-amplified clones from selected plants revealed intraspecific viral sequence variability, and also multiple begomovirus infections which could represent up to three species in a single tomato or cushaw plant. Phylogenetic grouping of virus sequences did not correlate with the host of origin.
Diseases caused by begomoviruses (family Geminiviridae, genus Begomovirus) constitute a serious c... more Diseases caused by begomoviruses (family Geminiviridae, genus Begomovirus) constitute a serious constraint to tomato production in Nicaragua. In this study, the complete nucleotide (nt) sequences of the DNA-A and DNA-B components were determined for the first time for Tomato leaf curl Sinaloa virus (ToLCSinV). In addition, the complete nt sequence was determined for the DNA-A component of two isolates of Tomato severe leaf curl virus (ToSLCV). The genome organization of ToLCSinV and ToSLCV was identical to the bipartite genomes of other begomoviruses described from the Americas. A phylogenetic analysis of DNA-A including 45 begomovirus species showed that the indigenous begomoviruses of the New World can be divided into three major clades and an intermediate group: AbMV clade, SLCV clade, “Brazil clade”, and BGYMV group. Phylogenetic analyses of the DNA-A and DNA-B components and their open reading frames indicated that ToLCSinV and ToSLCV belong to different clades: ToLCSinV to the AbMV clade, and ToSLCV to the SLCV clade. The two Nicaraguan isolates of ToSLCV showed a close relationship with ToSLCV from Guatemala (ToSLCV-[GT96-1]) and Tomato chino La Paz virus (ToChLPV), but differed significantly in the AV1 and AC1 regions, respectively. Computer-based predictions indicated that recombination with another begomovirus had taken place within AV1 of ToSLCV dividing this species into two strains. A high probability was also found that ToChLPV is involved in the evolution of ToSLCV.
and other tomato-growing areas of the world. The disease is caused by several virus species belon... more and other tomato-growing areas of the world. The disease is caused by several virus species belonging to the genus Begomovirus, family Geminiviridae that are transmitted by the whitefly Bemisia tabaci. There has been no previous information about which virus species/strains occur in tomatoes with TYLCD in Turkey. Therefore, polymerase chain reaction tests using degenerate primers were used to amplify partial sequences (579 bp) of the begomovirus coat protein gene (V1) from samples of diseased tomato plants collected from two major tomato-growing areas of Turkey (Mersin and Mug la). DNA sequence analyses of three isolates revealed high nucleotide sequence identities to isolates of Tomato yellow leaf curl virus (TYLCV, 97-98%) and tentatively identified them as belonging to that species. In addition, the complete nucleotide sequence was determined for one TYLCV isolate from Mersin (TYLCV-[TR:Mer6:04]). This isolate showed high nucleotide identity (98%) to isolates from the "prototype" strain of TYLCV, and only 92% identity to isolates of the TYLCV mild strain. A phylogenetic analysis confirmed that TYLCV-[TR:Mer6:04] belonged to the widespread "prototype" strain.
ANTECEDENTES HISTORICOS Desde antes de asumir la presidencia, el gobierno de Salvador Allende est... more ANTECEDENTES HISTORICOS Desde antes de asumir la presidencia, el gobierno de Salvador Allende estuvo marcada por un halo trágico. No sólo era la cuarta vez consecutiva que se presentaba a las elecciones presidenciales, sino que, la única vez que logró la mayoría de los votos (y con esto el cargo de presidente) fue con apenas un tercio de la población. A esto se le sumaba el hecho de que la clase que lo apoyaba no era la más influyente política ni económicamente. Con todos estos datos se podía predecir que la cuesta no se le haría fácil al líder comunista. Debería enfrentarse a dos tercios del país que eran opositores a su postura, entre los cuales se contaban los personajes más destacados e influyentes de la sociedad.
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